End face protection tape for fiber optic connector; and methods

ABSTRACT

Aspects and techniques of the present disclosure relate to a fiber optic connector assembly including a fiber optic connector with a front end and a back end. A ferrule positioned at the front end. The ferrule has a distal end face with a central region and recessed regions on opposite sides of the central region. The assembly includes a dust cap mounted on the ferrule. The dust cap has an open end and an opposite closed end. The fiber optic connector assembly also includes a tape member that covers the central region of the ferrule. The tape member can be secured to the dust cap such that when the dust cap is removed, the tape member simultaneously comes off with the dust cap.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a U.S. National Stage Application ofPCT/US2016/053053, filed on Sep. 22, 2016, which claims the benefit ofU.S. Patent Application Ser. No. 62/233,754, filed on Sep. 28, 2015, thedisclosures of which are incorporated herein by reference in theirentireties. To the extent appropriate, a claim of priority is made toeach of the above disclosed applications.

TECHNICAL FIELD

The present disclosure relates generally to optical fiber communicationsystems. More particularly, the present disclosure relates to fiberoptic connectors used in optical fiber communication systems. Thepresent disclosure also relates to a system for inspecting fiber-opticendfaces in multi-fiber connectors within an apparatus including amicroscope therein.

BACKGROUND

Fiber optic communication systems are becoming prevalent in part becauseservice providers want to deliver high bandwidth communicationcapabilities (e.g., data and voice) to customers. Fiber opticcommunication systems employ a network of fiber optic cables to transmitlarge volumes of data and voice signals over relatively long distances.Fiber optic connectors are an important part of most fiber opticcommunication systems. Fiber optic connectors allow optical fibers to bequickly optically connected without requiring a splice. Fiber opticconnectors can include single fiber connectors and multi-fiberconnectors.

A typical fiber optic connector includes a ferrule assembly supported ata distal end of a connector housing. The ferrule assembly can include amulti-fiber ferrule mounted in a hub. A spring is used to bias theferrule assembly in a distal direction relative to the connectorhousing. The multi-fiber ferrule functions to support the end portionsof multiple optical fibers. The multi-fiber ferrule has a distal endface at which polished ends of the optical fibers are located. When twomulti-fiber fiber optic connectors are interconnected, the distal endfaces of the multi-fiber ferrules oppose and are biased toward oneanother by their respective springs. With the multi-fiber fiber opticconnectors connected, their respective optical fibers are coaxiallyaligned such that the end faces of the optical fibers directly opposeone another. In this way, optical signals can be transmitted fromoptical fiber to optical fiber through the aligned end faces of theoptical fibers.

As indicated above, multi-fiber ferrules are configured for supportingthe ends of multiple optical fibers. Typically, the optical fibers arearranged in one or more rows within the multi-fiber ferrule. When twomulti-fiber ferrules are interconnected, the fibers of the rows ofoptical fibers align with one another. For most multi-fiber ferrules, itis desirable for the optical fibers to protrude distally outwardly fromthe distal end faces of the multi-fiber ferrules. This type ofprotrusion can assist in making physical fiber-to-fiber contact when twomulti-fiber connectors are mated. U.S. Pat. No. 6,957,920, which ishereby incorporated by reference in its entirety, discloses amulti-fiber ferrule having protruding optical fibers of the typedescribed above.

Contamination and defects on the end face of a fiber optical connectoris a major concern that can degrade the performance of the connector.For example, small scratches (e.g., on the order of micro-meters) anddust particles can greatly impact the performance of the connector.Accordingly, connectors are often transported and stored with end capsor dust covers that are designed to shield the end face of the connectorferrule. However, even with a dust cover, connectors may still becomecontaminated with particulates or become scratched. For example,particles from the interior of the dust cap may migrate to the end faceof the ferrule of the connector.

While structures such as dust caps have been used in the prior art toprotect the polished end faces of optical fibers, improvements aredesirable in this area.

SUMMARY

One aspect of the present disclosure relates to a fiber optic connector.The fiber optic connector can include a fiber optic connector having aconnector body with a front end and a back end. A ferrule can bepositioned at the front end of the connector body. The ferrule may havea distal end face with a central region and recessed regions on oppositesides of the central region. The ferrule can hold an optical fiber thathas a polished end face positioned at the central region of the distalend face of the ferrule. The fiber optic connector can also include adust cap mounted on the ferrule. The dust cap can have an open end andan opposite closed end such that the closed end of the dust cap opposesthe polished end face of the optical fiber. The fiber optic connectorcan also include a tape member that covers the central region of theferrule. The tape member can be secured to the dust cap such that whenthe dust cap is removed, the tape member simultaneously comes off withthe dust cap.

Another aspect of the present disclosure relates to fiber optic assemblythat can include a fiber optic connector with a ferrule. The ferrule cansupport an optical fiber extending therethrough to a distal end face ofthe ferrule. A dust cap can be mounted on the ferrule where the dust capcan have an open end and an opposite closed end. The closed end canoppose the distal end face of the ferrule. A tape cover can be adhereddirectly to the distal end face of the ferrule. The tape cover can beconnected to the dust cap such that the tape cover is simultaneouslyreleased with the dust cap as the dust cap is removed.

A further aspect of the present disclosure relates to an apparatus forapplying protective sheeting on an end face of a ferrule. The apparatuscan include an inspection device that includes a housing. The housingmay limit access of loose particles of dust and debris within it. Anintegrated tape dispenser can be located within the housing of theinspection device and the integrated tape dispenser can apply a tapemember to the end face of the ferrule while within the housing.

Another aspect of the present disclosure relates to a method of applyinga tape member to an end face of a ferrule connector positioned inside ahousing of an inspection device. The housing of the inspection devicecan include an integrated tape dispensing mechanism. The method caninclude the steps of inspecting an end face of the ferrule connectorwithin the housing of the inspection device; and applying the tapemember over the end face of the ferrule connector within the housing ofthe inspection device.

A variety of additional aspects will be set forth in the descriptionthat follows. The aspects relate to individual features and tocombinations of features. It is to be understood that both the foregoinggeneral description and the following detailed description are exemplaryand explanatory only and are not restrictive of the broad inventiveconcepts upon which the embodiments disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional top view of a pair of multi-fiber opticferrules in accordance with the principles of the present disclosure.

FIG. 2 is a cross-sectional view of the multi-fiber optic ferrule ofFIG. 1, as viewed along sight line A.

FIG. 3 is a side view of the female multi-fiber ferrule shown in FIG. 1.

FIG. 4 is an example apparatus including a tape application station inaccordance with principles of the present disclosure.

FIG. 5 is an end view of the apparatus shown in FIG. 4.

FIG. 6 is an end view of another ferrule connector with a tape memberapplied with a method in accordance with principles of the presentdisclosure.

FIG. 7 is a schematic side view of the ferrule connector shown in FIG.6.

FIG. 8 is a partial view of the apparatus shown in FIG. 4 depicting thetape application station and a ferrule.

FIG. 9 is a schematic view of a mechanism incorporated in the tapeapplication station shown in a raised position in accordance withprinciples of the present disclosure.

FIG. 10 is a schematic view of the mechanism shown in FIG. 9 in aplunged position in accordance with principles of the presentdisclosure.

DETAILED DESCRIPTION

The present disclosure relates generally to a process for applying tapeto an end face of a ferrule connector right after it has been inspectedas clean. The present disclosure incorporates a tape application stationinside of a housing of a microscope so that the inspection of the endface of the ferrule connector and the application of the tape to the endface of the ferrule connector can both occur within the housing in agenerally contaminated free area.

Fiber optic connectors can include ferrules supporting single opticalfibers (i.e., single-fiber ferrules corresponding to single-fiberconnectors) and can also include ferrules supporting multiple opticalfibers (i.e., multiple-fiber ferrules corresponding to multiple-fiberconnectors). One example of an existing single-fiber fiber opticconnection system is described at U.S. Pat. Nos. 6,579,014; 6,648,520;and 6,899,467, which are hereby incorporated by reference in theirentireties. An example of a multi-fiber connection system is disclosedat U.S. Pat. No. 5,214,730, the disclosure of which is herebyincorporated herein by reference in its entirety.

FIG. 1 illustrates an example female ferrule 10 and a male ferrule 12adapted to be coupled together. When the ferrules 10, 12 are coupledtogether (i.e., mated) optical fibers supported by the female ferrule 10are optically coupled to corresponding optical fibers supported by themale ferrule 12.

In some aspects, the female ferrule 10 and the male ferrule 12 each mayinclude a contact face 16 a, 16 b at a front end 18 a, 18 b of theferrules 10, 12. In some implementations, the female ferrule 10 and themale ferrule 12 may each define fiber passages 20 a, 20 b that extendthrough a depth of the female and male ferrules 10, 12 from a rear end22 a, 22 b of the female and male ferrules 10, 12 to the front end 18 a,18 b of the female and male ferrules 10, 12.

Referring to FIG. 2, in some aspects the fiber passages 20 a, 20 b maybe arranged in a row that extends along a major axis A₁ of the contactface 16 a, 16 b. In some aspects there may be multiple rows of fibers.The female ferrule 10 and the male ferrule 12 each may include aplurality of optical fibers 14 a, 14 b that extend through the fiberpassages 20 a, 20 b. Example optical fibers 14 a, 14 b include material(e.g., a glass core surrounded by a glass cladding layer) that transmitsoptical information/signals.

As depicted, the optical fibers 14 a may include an end face 24 a thatis accessible at the contact face 16 a at the front end 18 a of thefemale ferrule 10. The same can be said of the male ferrule 12. In use,the example optical fiber end faces 24 a, 24 b (not shown) may contacteach other to transmit optical signals between the optical fibers 14 a,14 b.

In some implementations, the female ferrule 10 and the male ferrule 12each may define a pair of alignment pin openings 26 a, 26 b (see FIG.1). In some aspects, the alignment pin openings 26 a, 26 b may extendrearwardly from contact face at the front end 18 a, 18 b of the femaleand male ferrules 10, 12. As depicted, the optical fibers 14 a, 14 b ofeach female and male ferrule 10, 12 may be positioned between each pairof alignment feature openings 26 a, 26 b.

In some implementations, the male ferrule 12 may include a pair ofalignment pins 28, for example a pair of alignment pins 28 with distalpoint contacts 30 that can be rounded distal tips, and proximal base endportions 32 positioned and supported within the alignment pin opening 26b. The proximal base end portions 32 may be permanently secured withinthe alignment pin openings 26 b.

Referring to FIG. 3, a side view of the female multi-fiber ferrule 10 isdepicted. The optical fibers 14 a can be potted within the fiberpassages 20 a. In one example, the optical fibers 14 a are potted withinthe fiber passages 20 a by bonding the optical fibers 14 a within thefiber passages 20 a using an adhesive such as epoxy.

Referring to FIGS. 4-5, an example apparatus 36 for applying a strip oftape (e.g., tape member, cover, or protective sheeting) on an end faceof a ferrule is shown. The apparatus 36 can include an inspection device40 (e.g., microscope) with a housing 38 and a tape application station42 including a mechanism for dispensing tape.

The housing 38 can help to limit access of loose particles such as dustor debris into the housing 38. Thus, the end face of the ferrule isprevented from being exposed to debris within the housing 38. In someaspects, a blower (not shown) may be used to continuously circulate airwithin the housing 38 to help keep the housing clean. The blower createspositive pressure within the housing 38 as compared to atmosphericpressure so that dust is prevented from entering. It draws air into thehousing chamber through an air intake filter. The blower causes acontinuous flow of air to exit the housing chamber through the openingfor receiving the fiber optic connector (i.e., the adapter port 44). Itcan also blow dust off an end face of a ferrule of a connector.

The housing 38 can define an adapter port 44 (see FIG. 5) for receivingan example ferrule connector 46 (e.g., fiber optic connector). Theferrule connector 46 may be pushed into the adapter port 44 to snaptherein such that an end face 48 of the ferrule connector 46 projectswithin the housing 38 for inspection. Once the ferrule connector 46 isinserted into the port 44 of the housing 38, end face 48 is exposed tothe inspection device and is ready for inspection.

In the depicted example, a portion of the inspection device 40 ispositioned within the housing 38. The inspection device 40 is anon-physical contact device that allows for magnified viewing of the endface 48 of the ferrule connector 46. The inspection device can include amicroscope having a lens that co-axially aligns with the ferrule of theferrule connector 46 when mounted at the adapter port 44 so that the endface 48 can be readily viewed for visual inspection.

The example tape application station 42 can include a plunger 50 that islocated within the housing 38 of the apparatus 36. The plunger 50 can bearranged and configured to apply a tape member 52 (see FIG. 6) to theend face 48 of the ferrule connector 46 directly inside the housing 38of the inspection device 40 to help limit contamination. Details of thetape application station 42 and the plunger 50 will be described in moredetail with reference to FIGS. 4, 9, and 10.

In the depicted example, the ferrule connector 46 can be either male orfemale. As shown in FIG. 6, the ferrule connector 46 is male having pins54 projecting from recessed guide pin holes. The same tape applicationstation 42 can be used for both male and female connectors because thetape member 52 is not needed for the recessed areas including the pins54. In other words, the whole end face 48 of the ferrule connector 46does not need to be covered which could otherwise pose a challenge withthe male connectors having the pins 54. While a multi-fiber connector isdepicted, the same principles can be applied to a single fiberconnector.

Referring to FIG. 7, a side schematic view of the example ferruleconnector 46 including a dust cap 56 thereon is depicted. The ferruleconnector 46 can have a connector body 41 with a front end 43 and a backend 45. A ferrule 47 can be positioned at the front end 43 of theconnector body 41. The ferrule 47 can have a distal end face 48 (seeFIG. 6) with a central region 49 and recessed regions 51 on oppositesides of the central region 49. The ferrule 47 can hold optical fibershaving a polished end face positioned at the central region 49 of thedistal end face 48 of the ferrule 47. In other aspects, the end face ofthe ferrule 47 can have an angled polish so that the surface between therecessed regions 51 and the pins 54 where the fibers pass through isangled.

The dust cap 56 has an open end 53 and an opposite closed end 55. Theclosed end 55 of the dust cap 56 opposing the polished optical fiber endfaces 24 a.

The optical fiber end face 58 of the ferrule connector 46 is covered orprotected by the tape member 52 at the central region 49. The tapemember 52 can be applied between the pins 54 such that the tape member52 has end edges 60 that hang over longitudinal sides 62 of the end face48 of the ferrule connector 46.

In one aspect, the tape member 52 can be engineered to be constructedwith a desired thickness, hardness, and size. The dust cap 56 can beapplied over the ferrule connector 46 such that the end edges 60 of thetape member 52 flex downwardly as the dust cap 56 is secured thereon.The tape member 52 is flexible enough that it flexes along its lengthwhen the dust cap 56 is inserted over the ferrule connector 46 and sidewalls 66 of the dust cap 56 engage the end edges 60 of the tape member52, but stiff enough that the end edges 60 dig into or embed in the sidewalls 66 of the dust cap 56 (which can be made of a rubber material)when the dust cap 56 is removed from the ferrule connector 46. Thus, thetape member 52 can stay mechanically fixed (e.g., locked, coupled,attached) with respect to the dust cap 56 when the dust cap 56 isremoved from the ferrule connector 46.

The configuration of the tape member 52 inside the dust cap 56 can allowthe tape member 52 to be simultaneously released from the optical fiberend face 58 as the dust cap 56 is removed. In other examples, the dustcap 56 can include a pre-applied pressure sensitive adhesive on the sidewalls 66 thereof such that the tape member 52 adheres to the dust cap 56when placed over the ferrule connector 46. The pre-applied pressuresensitive adhesive can have a higher bond strength than the tape member52 so that the tape member 52 is removed with the removal of the dustcap 56.

In other aspects, the tape member 52 can be configured to remain inplace when the dust cap 56 is removed. The tape member 52 can beconfigured to attach to a variety of dust caps without any specialdesign requirement. For example, tape can be fixedly attached within acylindrical dust cap adapted to cover a single fiber ferrule. The tapecan be affixed at a base end of the cylindrical dust cap using anattachment technique that allows the tape to be carried with the dustcap when the dust cap is removed from a ferrule. The tape can bepre-mounted in the dust cap so that the tape is applied to an end faceof the ferrule when the dust cap is inserted over the ferrule. In oneaspect, the tape member 52 can include a coloring agent for easyidentification. The tape member 52 may also be transparent to be able tosee through it for inspection of, for example, air bubbles.

Turning to FIG. 4 again, the tape application station 42 can include asupply spool 68 (e.g., feel roller) that has a film 82 (see FIG. 9)including a backing sheet 70 (e.g., liner) with individually cut piecesof the tape member 52 thereon, a rewind spool 72 (e.g., rewind roller)for collecting the backing sheet 70, and an actuator 74 for advancingthe supply spool 68, and the plunger 50 that is arranged and configuredto apply the cut tape member 52 onto the optical fiber end face 58 ofthe ferrule connector 46.

In one example, the tape member 52 can be die cut or mechanically cutinside the apparatus 36 in line into separate pieces on the backingsheet 70. Other cutting mechanisms may be used, such as, but not limitedto, laser cutting, etching. In other examples, the tape member 52 can becut separately outside of the tape application station 42.

In use, the actuator 74 can be pushed down automatically or manually topivot about one or more pivot points which pushes the plunger 50 up anddown. As the actuator 74 is pressed, it can advance the supply spool 68and the plunger 50, including the film 84, can be forced downward into aplunged position (see FIG. 10). In the plunged position, the plunger 50may be indexed to apply the tape member 52 directly onto the opticalfiber end face 58 of the ferrule connector 46. After the tape member 52is applied, the plunger 50 can then be raised upward in a raisedposition (see FIG. 9) and the cycle repeated.

FIG. 8 is an exploded view of the tape dispenser 50 shown in FIG. 4. Inone aspect, the plunger 50 can include a frame 76. The plunger 50 caninclude a tape application arrangement 90 as shown in FIGS. 9 and 10.

FIGS. 9 and 10 depict an example mechanism for the tape applicationarrangement 90 that can be incorporated inside the plunger 50. It willbe appreciated that other arrangements may be used. In FIG. 9, theplunger 50 is schematically shown in a raised position. The supply spool68 is shown supplying the film 82 with the backing sheet 70 and cutpieces of the tape member 52 thereon. The film 82 can be feed throughthe tape dispenser 50 and a guide roller 80 may be used to help guidethe film 82 therethrough. In the tape application arrangement 90, thefilm 82 can be routed through the tape dispenser 50 over a tight radiusroller 84. The tight radius roller 84 can have a bend radius smallenough such that the tape member 52 separates from the backing sheet 70as it moves around. The tight radius roller 84 can be referred to a tapeseparation structure and can be a roller or other structure having astight bend or profile suitable for causing the tape to unpeel/disengagefrom the backing sheet 70. A return roller 86 can be used to return thebacking sheet 70 back to the rewind spool 72.

FIG. 10 is a schematic view of the plunger 50 in the plunged position. Aspring loaded roller 88 (i.e., tape press roller or other pressingstructure) is shown on an arm 89 to press the tape member 52 on theoptical fiber end face 58 of the ferrule connector 46. As shown, thespring loaded roller 88 presses against the tape member 52 and rollsthereon as the plunger 50 is raised. In other embodiments, the pressroller does not have to be on an arm or be spring loaded to apply thetape member 52.

The present disclosure also relates to a method of applying a tapemember to an end face of a ferrule connector positioned inside a housingof an inspection device, the housing of the inspection device having anintegrated tape dispensing mechanism therein. The method can include thesteps of inspecting an end face of the ferrule connector within thehousing of the inspection device and applying the tape member over theend face of the ferrule connector within the housing of the inspectiondevice.

From the forgoing detailed description, it will be evident thatmodifications and variations can be made without departing from thespirit and scope of the disclosure.

What is claimed is:
 1. A fiber optic connector assembly comprising: afiber optic connector having a connector body with a front end and aback end; a ferrule positioned at the front end of the connector body,the ferrule having a distal end face with a central region and recessedregions on opposite sides of the central region, the ferrule holding anoptical fiber having a polished end face positioned at the centralregion of the distal end face of the ferrule; a dust cap adapted tomount on the ferrule, the dust cap having an open end and an oppositeclosed end, the closed end of the dust cap being configured to opposethe polished end face of the optical fiber; and a tape member coveringthe central region of the ferrule such that end edges of the tape memberhang over longitudinal sides of the distal end face of the ferrule,while the dust cap is being inserted over the fiber optic connector, theend edges of the tape member are adapted to flex downwardly to secure toside walls of the dust cap such that, as the dust cap is removed, thetape member simultaneously comes off with the dust cap.
 2. The fiberoptic connector assembly of claim 1, wherein the tape member contains acoloring agent.
 3. The fiber optic connector assembly of claim 2,wherein the tape member is transparent.
 4. The fiber optic connectorassembly of claim 1, wherein the dust cap has side walls that extendfrom the open end to the closed end of the dust cap.
 5. The fiber opticconnector assembly of claim 1, wherein the end edges of the tape memberare configured to embed in the side walls of the dust cap.
 6. A fiberoptic assembly comprising: a fiber optic connector comprising a ferrule,the ferrule supporting an optical fiber extending therethrough to adistal end face of the ferrule; a dust cap adapted to mount over theferrule, the dust cap having an open end and an opposite closed end, theclosed end opposing the distal end face of the ferrule; and a tape coveradhered directly to the distal end face of the ferrule such that endedges of the tape cover hang over longitudinal sides of the distal endface of the ferrule, while the dust cap is being inserted over the fiberoptic connector, the end edges of the tape cover are adapted to flexdownwardly to attach to side walls of the dust cap such that the tapecover is simultaneously released with the dust cap as the dust cap isremoved.
 7. The fiber optic assembly of claim 6, wherein the tape covercontains a coloring agent and is transparent.
 8. The fiber opticassembly of claim 6, wherein the end edges of the tape cover areconfigured to embed in the side walls of the dust cap.